Tehran - Iranian President Mahmoud Ahmadinejad paid tribute to late Venezuelan leader Hugo Chavez on Wednesday saying he had fallen "martyr" to a "suspect illness".
Ahmadinejad hailed his close ally for "serving the people of Venezuela and defending human and revolutionary values".
"He finally died from a suspect illness and he gave his life... to the elevation of his country and the freedom of his people," Ahmadinejad said in a message of condolences to Vice President Nicolas Maduro.
The Iranian president was backing claims made by Maduro shortly before Chavez's death was announced that Venezuela's enemies had somehow afflicted the firebrand leftist with the cancer that eventually killed him.
"Venezuela lost its brave, strong son and the world lost a wise and revolutionary leader," Ahmadinejad added.
"I have no doubt that he will return, along with the righteous Jesus and the perfect human."
Day of mourning
The last was a reference to Shiite Islam's 12th imam that Iran's majority faith believes will return with Christ to bring peace and justice to the world.
Ahmadinejad said it was a "possibility" that he would attend Chavez's funeral, the ISNA news agency reported.
A cabinet meeting chaired by the president declared Wednesday a day of mourning in Iran, the state television website said.
Iran and Venezuela have both pursued strongly anti-American foreign policies and have signed billions of dollars in investment agreements in recent years.
Chavez made 13 visits to Iran between 1999 and his death on Tuesday. Ahmadinejad has made six visits to Venezuela since 2005.